Lathe-clamp or the like.



G. AMBORN.

LATHE CLAMP OR THE LIKE.

- APPLICATION FILED 1mm, 1912.

Patented Apr. 1, 1918.

INVENTOR By A Ztm'neys, Wm

NOGRAPH CO. WASHINGTON, D C. I

COLUMBIA PLA WITNESSES:

. monly employed State of Connecticut, have UNTTED STATEG PATENT@Flfilftllfl.

GEORGE AMBOBN, OF GHAPINVILLE, CONNECTICUT, ASSIGNOIR TO J. H. VIILLIAMS& (30., OF BROOKLYN, NEW YORK, A CORPORATION OF NEW YORK.

LATHE-CLAMP OR THE LIKE.

Specification of Letters Patent.

Patented Apr. i, @9133.

Application filed February 8, 1912. Serial No. 676,412.

To all whom it may concern:

Be it known that I, GEORGE AMBonN, a citizen of the United States,residing. in Chapinville, in the county of Litchfield and inventedcertain new and useful Improvements in Lathe- Clamps or the Like, ofwhich the following is a specification.

This invent-ion relates to lathe clamps or the like, and aims to providecertain improvements therein. In devices of this type two clampingmembers are provided, one of which usually carries a shank or tail bywhich the clamp is connected with a lathe or other machine. In the typeof clamp comthe clamping members are held in engagement with the work bya pair of screw-threaded bolts which pass through smooth bores or holesin one of the clamping members and have a screw-threaded connection withthe other member. The result of this construction is that when the clampis used on thin work the screw threaded bolts project for the majorportion of their length a considerable distance beyond one of themembers. When the work is mounted concentrically in a lathe or otherrotating tool, the screws move in a circular ath which is of relativelylarge diameter and this frequently results in accidents to the workmen,particularly. when the work is being filed or finished by hand tools. Efforts have been made to minimize this disadvantage by constructing thescrews with right and left threads, but this has necessitated theprovision of wrench or other turning tool faces between the clamps. Withthis construction when the work is wide the wrench faces are not easilyaccessible so that it is difiicult to tighten the clamp. Theconstruction also introduced complications in shape which are necessaryon account of the space taken up by the wrench faces.

According to the present invention I provide a clamp of this type inwhich when the clamp is used for thin work both ends of the screws mayextend equi-distantly beyond the clamps so that the circle described bythe entire tool is much reduced in diameter.

In the accompanying drawings which illustrate one form of theinvention,-Figure 1 is a side elevation, partly in section, of thepreferred form of the invention. Fig. 2 is a bottom or under side viewof Fig. 1.

Fig. 3 is an elevation at right angles to Fig. 1.

Referring to the drawings, let A B represent the clamp plates, one ofwhich as B is provided with a shank or tail C, usually curved, so thatits end extends at right angles to the body of the clamp. The clamps areadjusted to and from each other by members D D which are best made asscrew -threaded bolts adapted to pass through unthreaded holes E E inone of the members as for instance A, and to engage screw-threaded holesF F in the opposite member. Each of the bolts D D is provided with a nutor equivalent device G which in the construction illustrated is locatedon the outer side of the member A Preferably also the bolts are formedwith provisions by which they may be turned either by hand or by asuitable tool. These provisions preferably comprise knurled heads I-Ilocated at the ends of the bolts which project from the member A,although they may be located elsewhere as at the opposite ends ifdesired. The construction shown is preferred for the reason that theheads constitute stops which prevent the unscrewing of the nuts G 01fthe bolts, so that they can not be lost or misplaced.

In the use of the tool the workman gages the thickness of the workandrotates the screw bolts by hand to such position that the ends of thebolts extend beyond the clamp B to about the same extent that theyextend beyond the opposite clamp, whereupon the nuts G are tightened bythe use of a wrench until the work is firmly clamped. By this means theparts of the clamp extend as little possible beyond the center of thework, so that the circle described by the clamp is reduced to theminimum. Furthermore, the nuts G or equivalent adjusting devices arelocated beyond the working faces of the clamps so that the work, nomatter what its dimensions, does not interfere with the accessibility ofthe nuts. Moreover, the working faces of the clamps may be straight,flat, or of other simple shape, since the necessity of interveningwrench faces on the bolts is avoided.

I/Vhile I have shown in detail the preferred construction of theinvention, it will be understood that I do not wish to be limitedthereto, as various changes can be made therein without departing fromthe invention.

That I claim is 1. In a lathe clamp or the like, the com bination of apair of clamp plates, and means for adjusting the distance of each ofsaid clamp-plates from a fixed center, said means comprising boltsadjustable with relation to one of said clamps, and means for adjustingthe other of said clamp plates upon said bolt so that the ends of saidbolts may extend substantially equi-distantly beyond both the clampplates.

2. In a lathe clamp or the like, the combination of a pair of clampplates, and means for adjusting the distance of each of saidclamp-plates from a fixed center, said means comprising bolts foradjusting said clamp plates, said bolts each having a threadedengagement with one of said plates,

and a loose engagement with the other of said clamp plates, and nuts onsaid bolts engaging said other clamp plat-es and adapted to sustain thepull of said bolts on said clamp plates.

3. In a lathe clamp or the like, the combination of a pair of clampplates, bolts each having a threaded engagement with one of said platesand a loose engagement with the other of said plates, nuts on said boltsbeyond the clamp plate which is loosely engaged by said bolts, and headsbeyond said nuts.

In witness whereof, I have hereunto signed my name in the presence oftwo subscribing witnesses.

GEORGE AMBORN.

Witnesses:

CHARLES B. HARRIS, WILLIAM G. COLE.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents,

Washington, D. G.

